Organ transplantation is a viable therapy for improving the quality of life in people with end-stage organ failure. Progress has been made in using bone marrow, kidneys, hearts, and livers from unrelated individuals, though transplant rejection remains a persistent problem. Another limiting factor in clinical transplantation is the persistent shortage of organs. For example, of the 265,000 patients with end-stage kidney disease in the U.S., only 5-6% will receive a transplant. Hepatitis C virus-related liver diseases is another source of increasing demand for liver transplants, whose incidence is on the rise with predictions reaching increases of at least five-fold in the next decade.
Typically, organ donors are heart-beating cadaver donors (HBD), which unfortunately, represent a supply source remaining relatively constant for the past ten years.
Organ rejection is a product of the immune system of the recipient, which recognizes the transplant as foreign tissue and develops immune reactivity, culminating in rejection of the transplanted/grafted tissue. Attempts to tolerize recipients to transplant tissue have not met with much success to date.
Early detection of transplant rejection affords the possibility of aggressive immunosuppressive therapy for preventing transplant rejection. Methods for predicting transplant tolerance are clearly desirable for both diminishing potentially, the amount/duration of immunosuppressive therapy in successful recipients, and increasing the likelihood of successful transplantation in a particular recipient with respect to a given donor.
With the limited donor-pool, the criticality of donor choice and the clinical and economical consequences of transplant rejection, it is apparent, that new and inproved methods for predicting the probability of transplant rejection are greatly needed.